As if we needed another reason to remind you to be wary of health advice you find on YouTube, a new article in the Daily Mail reveals a disturbing and potentially dangerous method of DIY plastic surgery. The story highlights a “growing number of tutorials” on the video site about how to remove keloids—large scar-tissue growths—by cutting off their blood supply with a rubber band.

The videos are graphic: They depict people wrapping rubber bands tightly around keloids on their earlobes and show how the scar tissue turns black, shrivels up, and falls off over the course of a few days. Several of the videos, like the one below, have racked up more than 150,000 views. Watch at your own risk!

Besides being visually alarming, the at-home removal method has doctors concerned. To learn more about keloids—and the right (and wrong) ways to remove them—Health spoke with Jared Liebman, MD, a plastic surgeon with Einstein Healthcare Network in Philadelphia. Here’s what he wants anyone viewing those videos to know.

What are keloids, anyway?

A keloid is a type of scar tissue that grows beyond the border of its original wound, explains Dr. Liebman. They can form anywhere on the body where an injury to the skin has occurred, but one very common spot is on the earlobe, after a piercing.

“Some things that can lead to keloids can include dirty or infected surgical sites, or similar procedures or interventions,” says Dr. Liebman. “Tattoos and piercings can be a common cause because they may be a little less than sterile.” Earrings (or other piercings) made with inexpensive metal alloys can also trigger allergic reactions that can cause keloids.

Some people—and some ethnic groups, including African Americans, Asians, and Pacific Islanders—are genetically predisposed to developing keloids. In extreme cases, they can form after even the slightest trauma to the skin.

“For someone with a very high genetic susceptibility, it could be anything that sets up a scar pattern—like an insect bite, or scraping your arm against a brick wall,” says Dr. Liebman. “I’ve had patients who come in with keloids all over their body and they don’t know what the injuries were that caused them.”

Rubber-band removal may work, but it’s not safe

The YouTube trick in question works like this: A rubber band is wrapped tightly around the unwanted growth, essentially forming a tourniquet and cutting off blood and oxygen to the tissue. Within a few days, according to the videos, the keloid becomes black and eventually falls off.

The idea behind this is based in real medical procedures, says Dr. Liebman; in fact, it’s similar to a procedure called a vascular clip still used today when babies are born with extra digits. That’s definitely not an endorsement, though.

“The technique itself is not necessarily bad, but it’s dangerous to undertake any type of surgical technique on your own,” he says. “If you don’t have proper background knowledge, the potential for complications is much higher.”

Removing an earlobe keloid in this way can leave exposed cartilage, he says, which could lead to significant ear deformities. “You could have an issue where the cartilage gets infected and doesn’t heal well,” he says, “and that would typically require aggressive surgical treatment to remove that part of the ear.”

Keloids also have a very high recurrence rate, especially when they’re not removed in a sterile environment the first time. “The likelihood that that keloid would grow back is pretty high in these circumstances,” says Dr. Liebman.

So what should you do with a keloid?

To be honest, says Dr. Liebman, there’s not a lot of great research on keloid removal and what works best; that’s because keloids seem to be unique to humans, so there’s no good way to study them (or their remedies) on animals.

But there are a few procedures that can be performed by a dermatologist or plastic surgeon that seem to work well, he adds. A doctor may recommend a compression device—a clip-on device that applies pressure to the affected tissue—that can help the keloid get smaller or fall off on its own. Steroid injections, surgical removal, or radiation treatments can also be used to shrink or remove keloids.

Having these procedures done by a medical professional can ensure that they’re sterile and can reduce the risk of infection or recurrence, says Dr. Liebman. A doctor can also advise, based on your personal and family history of keloids, which method of removal may work best.

“People should definitely start by addressing their primary care doctor or some other health-care professional,” says Dr. Liebman. “Scar-revision treatments are generally considered cosmetic and aren’t covered by insurance, but if it’s a true keloid—when it’s large and irregular and potentially deforming—companies will often make an exception.”

You can also reduce your risk of developing keloids by avoiding piercings and tattoos, or by researching facilities that perform these services ahead of time. “Make sure the shop is using good, sterile techniques and it’s a clean environment,” says Dr. Liebman. “If you’re getting a piercing, I would also strongly recommend using a precious metal.” Specifically, he suggests solid gold (not gold plated), sterling silver, or surgical-grade stainless steel.

Dr. Liebman hasn’t had any patients ask him about this particular DIY remedy, but he’s not surprised that people have attempted this type of treatment at home. “I had one patient who tried to treat something on her lip with an apple-cider vinegar mixture and she ended up with a horrendous burn,” he says. “Just because you see something on the Internet doesn’t mean you should try it yourself.”